CN103227474B - A kind of photovoltaic power generation grid-connecting system based on solid-state transformer - Google Patents

A kind of photovoltaic power generation grid-connecting system based on solid-state transformer Download PDF

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Publication number
CN103227474B
CN103227474B CN201210021859.1A CN201210021859A CN103227474B CN 103227474 B CN103227474 B CN 103227474B CN 201210021859 A CN201210021859 A CN 201210021859A CN 103227474 B CN103227474 B CN 103227474B
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solid
phase
state transformer
inverter
power switching
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CN103227474A (en
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张明锐
林承鑫
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Tongji University
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Tongji University
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/56—Power conversion systems, e.g. maximum power point trackers

Abstract

The present invention relates to a kind of photovoltaic power generation grid-connecting system based on solid-state transformer, comprise photovoltaic array, solid-state transformer, output filter, load and electrical network, described solid-state transformer is connected with photovoltaic array, output filter, load respectively, and described output filter is connected with electrical network.Compared with prior art, the present invention has that stability is high, strong interference immunity, dynamic response are fast, can realize the advantages such as energy in bidirectional flow.

Description

A kind of photovoltaic power generation grid-connecting system based on solid-state transformer
Technical field
The present invention relates to a kind of photovoltaic power generation grid-connecting system, especially relate to a kind of photovoltaic power generation grid-connecting system based on solid-state transformer.
Background technology
In recent years along with the decline of photovoltaic cell cost and the raising of photovoltaic efficiency, the application prospect of photovoltaic generation is unprecedentedly wide, and photovoltaic power generation grid-connecting is the important development direction of photovoltaic generation, compared with independent photovoltaic generating system, can energy storage device be saved, more intensively utilize solar energy; But because photovoltaic generation has randomness, intermittent, periodically, make the fail safe of grid-connected photovoltaic power station and connecting system thereof, reliability faces new test.
The circuit structure of photovoltaic power generation grid-connecting system classics is divided into single stage type transless structure, the two-stage type structure of band Industrial Frequency Transformer isolation and the multistage structure of band high frequency transformer isolation; Adopt one of object of single stage type transless structure to be that structure is simple, cost is low, and efficiency is high, but input and output do not have electrical isolation, and input voltage range is little, controls underaction; Adopt the two-stage type structure control of band Industrial Frequency Transformer isolation more flexible, step-up ratio is large, achieve electrical isolation, but the existence of Industrial Frequency Transformer adds equipment cost and volume; For overcoming this defect, occurred again the multistage structure being with high frequency transformer isolation, but this structural circuit is complicated, is suitable only for small-power occasion, needing is boosted by Industrial Frequency Transformer just can be incorporated to 10kV electrical network.
Summary of the invention
Object of the present invention be exactly provide that a kind of stability is high to overcome defect that above-mentioned prior art exists, strong interference immunity, dynamic response are fast, the photovoltaic power generation grid-connecting system based on solid-state transformer that can realize energy in bidirectional flow.
Object of the present invention can be achieved through the following technical solutions:
A kind of photovoltaic power generation grid-connecting system based on solid-state transformer, it is characterized in that, comprise photovoltaic array, solid-state transformer, output filter, load and electrical network, described solid-state transformer is connected with photovoltaic array, output filter, load respectively, and described output filter is connected with electrical network.
Described solid-state transformer comprises the three-phase fully-controlled rectifier, DC-DC converter, the DC-AC inverter that connect successively, and the output of described photovoltaic array is connected between three-phase fully-controlled rectifier, DC-DC converter;
The output electric energy of described photovoltaic array preferentially by after three-phase fully-controlled rectifier for load, if the output electric energy of photovoltaic array is greater than electric energy needed for load, by remaining electric energy successively by being input to electrical network after DC-DC converter, DC-AC inverter, output filter.
Described DC-DC converter comprises the low-pressure side DC capacitor, single-phase full-bridge inverter, high frequency transformer, single-phase full bridge rectifier, the high-pressure side DC capacitor that connect successively; Described DC-AC inverter is three-phase half-bridge inverter.
Described three-phase fully-controlled rectifier comprises six device for power switching and is connected in parallel on the diode at device for power switching two ends; Described single-phase full-bridge inverter comprises four device for power switching and is connected in parallel on the diode at device for power switching two ends; Described single-phase full bridge rectifier comprises four device for power switching and is connected in parallel on the diode at device for power switching two ends; Described three-phase half-bridge inverter comprises six device for power switching and is connected in parallel on the diode at device for power switching two ends.
Described device for power switching is IGBT, IGCT or MOSFET.
Described output filter is LC filter or LCL filter.
Described single-phase full-bridge inverter and single-phase full bridge rectifier all adopt PWM to control.
Described DC-AC inverter adopts voltage, current double closed-loop control strategy, and in conjunction with synchronization phase-locked control technology, realizes grid-connected current and the same homophase frequently of line voltage.
Compared with prior art, the present invention has the following advantages:
1, adopt the boosting link of high frequency transformer isolation, eliminate bulky Industrial Frequency Transformer, it controls more flexible, while realizing electric pressure conversion, reach electrical isolation object;
2, inversion link DC-side Voltage Stabilization, overcomes the adverse effect that photovoltaic array output-power fluctuation causes system, realizes current on line side sineization and for unit power factor;
3, system rejection to disturbance is strong, and dynamic response is fast, can realize energy in bidirectional flow;
4, be suitable for large-scale photovoltaic electricity generation grid-connecting, do not need Industrial Frequency Transformer just can realize 10kV high pressure grid-connected.
Accompanying drawing explanation
Fig. 1 is structural representation of the present invention;
Fig. 2 is the structural representation of DC-DC converter of the present invention;
Fig. 3 is the structural representation of three-phase fully-controlled rectifier of the present invention;
Fig. 4 is the structural representation of three-phase half-bridge inverter of the present invention;
Fig. 5 is cutting-in control principle schematic of the present invention.
Embodiment
Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.
Embodiment
As shown in Figure 1, a kind of photovoltaic power generation grid-connecting system based on solid-state transformer, comprise photovoltaic array 1, solid-state transformer 2, output filter 3, load 4 and electrical network 5, described solid-state transformer 2 is connected with photovoltaic array 1, output filter 3, load 4 respectively, and described output filter 3 is connected with electrical network 5.Described solid-state transformer 2 provides different electric pressure interface, various distributed power source, and load 4 and energy storage device etc. can access different voltage bus as required, realize generating, transmission of electricity, the unified management of electricity consumption and Optimum utilization are a kind of ideal styles of following renewable energy utilization.For the feature of photovoltaic power generation grid-connecting system self, the present invention overcomes the adverse effect that photovoltaic array output-power fluctuation causes system, and program fast response time has good anti-interference, realizes current on line side sineization and for unit power factor (PF).
As shown in Figure 1, described solid-state transformer 2 comprises the three-phase fully-controlled rectifier 21, DC-DC converter 22, the DC-AC inverter 23 that connect successively, and the output of described photovoltaic array 1 is connected between three-phase fully-controlled rectifier 21, DC-DC converter 22;
The output electric energy of described photovoltaic array 1 is preferentially rear for load by three-phase fully-controlled rectifier 21, if the output electric energy of photovoltaic array is greater than electric energy needed for load, by remaining electric energy successively by being input to electrical network 5 after DC-DC converter 22, DC-AC inverter 23, output filter 3.
As shown in Figure 2, described DC-DC converter 22 comprises the low-pressure side DC capacitor 224, single-phase full-bridge inverter 221, high frequency transformer 222, single-phase full bridge rectifier 223, the high-pressure side DC capacitor 225 that connect successively; Described DC-AC inverter 23 is three-phase half-bridge inverter.
As shown in Figure 3, Figure 4, described three-phase fully-controlled rectifier 21 comprises six device for power switching (S21, S22, S23, S24, S25, S26) and is connected in parallel on the diode (D21, D22, D23, D24, D25, D26) at device for power switching two ends; Described single-phase full-bridge inverter comprises four device for power switching (S11, S12, S13, S14) and is connected in parallel on the diode (D11, D12, D13, D14) at device for power switching two ends; Described single-phase full bridge rectifier comprises four device for power switching (D15, D16, D17, D18) and is connected in parallel on the diode (S15, S16, S17, S18) at device for power switching two ends; Described three-phase half-bridge inverter comprises six device for power switching (S31, S32, S33, S34, S35, S36) and is connected in parallel on the diode (D31, D32, D33, D34, D35, D36) at device for power switching two ends.Described device for power switching is IGBT, IGCT or MOSFET, described diode be IGBT body in diode, IGCT body in diode, MOSFET body in diode or external diode.Described output filter is LC filter or LCL filter.High frequency transformer selects amorphous alloy material as core material, and its major function realizes voltage transformation, and energy transferring and electrical equipment isolation, significantly reduce the volume and weight of solid-state transformer simultaneously.
Operational mode of the present invention is: when energy flows from photovoltaic array to electrical network, the direct current that photovoltaic array exports is after the voltage stabilizing of low-pressure side DC capacitor, the 700V DC interface that access solid-state transformer provides, high frequency low voltage alternating current is modulated into by single-phase full-bridge inverter, be high-frequency and high-voltage alternating current by high frequency transformer boosting inverter again, then 18kV high voltage direct current is reduced into through a single-phase full bridge rectifier, be transformed to the industrial-frequency alternating current of 10kV finally by output three-phase half-bridge inverter, after filtering, be incorporated to 10kV electrical network.
The control objectives being applicable to the above-mentioned photovoltaic power generation grid-connecting system based on solid-state transformer is as follows: keep DC side voltage of converter to stablize, and ensure that net side unity power factor runs, output current is sinusoidal wave and harmonic component is little.
The control method that DC-DC converter is concrete is: this link directly adopts opened loop control, and single-phase full-bridge inverter and single-phase full bridge rectifier all adopt PWM to control, drive singal to be duty ratio be 50% complementary trigger impulse.
The concrete control method of DC-AC inverter is as shown in Figure 5: adopt voltage, current double closed-loop control strategy, and in conjunction with synchronization phase-locked control technology, realize grid-connected current with line voltage with frequency homophase.DC bus-bar voltage U dcafter sampling, carry out application condition with DC reference voltage, error signal obtains reference current after PI regulates again with i dcarrying out application condition, then regulate through PI, just can obtain u by calculating d, can u be calculated equally q, by u d, u qand the angle that phase locking unit obtains just can produce sinusoidal modulation wave, then produce the control signal of inverter through logic drive circuit.

Claims (5)

1. the photovoltaic power generation grid-connecting system based on solid-state transformer, it is characterized in that, comprise photovoltaic array, solid-state transformer, output filter, load and electrical network, described solid-state transformer is connected with photovoltaic array, output filter, load respectively, and described output filter is connected with electrical network;
Described solid-state transformer comprises the three-phase fully-controlled rectifier, DC-DC converter, the DC-AC inverter that connect successively, and the output of described photovoltaic array is connected between three-phase fully-controlled rectifier, DC-DC converter;
The output electric energy of described photovoltaic array preferentially by after three-phase fully-controlled rectifier for load, if the output electric energy of photovoltaic array is greater than electric energy needed for load, by remaining electric energy successively by being input to electrical network after DC-DC converter, DC-AC inverter, output filter; Described DC-DC converter comprises the low-pressure side DC capacitor, single-phase full-bridge inverter, high frequency transformer, single-phase full bridge rectifier, the high-pressure side DC capacitor that connect successively; Described DC-AC inverter is three-phase half-bridge inverter; Described DC-AC inverter adopts voltage, current double closed-loop control strategy, and in conjunction with synchronization phase-locked control technology, realizes grid-connected current and the same homophase frequently of line voltage;
When energy flows from photovoltaic array to electrical network, the direct current that photovoltaic array exports is after the voltage stabilizing of low-pressure side DC capacitor, the 700V DC interface that access solid-state transformer provides, high frequency low voltage alternating current is modulated into by single-phase full-bridge inverter, be high-frequency and high-voltage alternating current by high frequency transformer boosting inverter again, then 18kV high voltage direct current is reduced into through a single-phase full bridge rectifier, be transformed to the industrial-frequency alternating current of 10kV finally by output three-phase half-bridge inverter, after filtering, be incorporated to 10kV electrical network.
2. a kind of photovoltaic power generation grid-connecting system based on solid-state transformer according to claim 1, is characterized in that, described three-phase fully-controlled rectifier comprises six device for power switching and is connected in parallel on the diode at device for power switching two ends; Described single-phase full-bridge inverter comprises four device for power switching and is connected in parallel on the diode at device for power switching two ends; Described single-phase full bridge rectifier comprises four device for power switching and is connected in parallel on the diode at device for power switching two ends; Described three-phase half-bridge inverter comprises six device for power switching and is connected in parallel on the diode at device for power switching two ends.
3. a kind of photovoltaic power generation grid-connecting system based on solid-state transformer according to claim 2, it is characterized in that, described device for power switching is IGBT, IGCT or MOSFET.
4. a kind of photovoltaic power generation grid-connecting system based on solid-state transformer according to claim 1, it is characterized in that, described output filter is LC filter or LCL filter.
5. a kind of photovoltaic power generation grid-connecting system based on solid-state transformer according to claim 1, it is characterized in that, described single-phase full-bridge inverter and single-phase full bridge rectifier all adopt PWM to control.
CN201210021859.1A 2012-01-31 2012-01-31 A kind of photovoltaic power generation grid-connecting system based on solid-state transformer Expired - Fee Related CN103227474B (en)

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Publication number Priority date Publication date Assignee Title
CN103490500A (en) * 2013-09-13 2014-01-01 嘉兴凯希电子有限公司 Multifunctional renewable energy source converting system
CN103490467A (en) * 2013-09-13 2014-01-01 嘉兴凯希电子有限公司 Charging and discharging controller
CN104578166A (en) * 2015-01-29 2015-04-29 国家电网公司 Alternating current-direct current micro-grid system on basis of electricity energy collector
CN104993713A (en) * 2015-07-22 2015-10-21 太原理工大学 Control method for double PWM solid-state transformer

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000010648A (en) * 1998-06-18 2000-01-14 Canon Inc Electric power controller, and photovoltaic power generation system using the same
CN1794549A (en) * 2006-01-01 2006-06-28 福州大学 Step-up high frequency link A-A transducer
CN101615847A (en) * 2009-07-23 2009-12-30 东南大学 Automatic voltage regulator based on electric power electric transformer
US7679941B2 (en) * 2007-06-06 2010-03-16 General Electric Company Power conversion system with galvanically isolated high frequency link
CN101777775A (en) * 2010-02-26 2010-07-14 东南大学 High-frequency isolation single-phase photovoltaic grid-connected system and control method thereof
CN101917126A (en) * 2010-07-30 2010-12-15 浙江大学 Voltage-equalizing and power-equalizing control method for multi-module cascade solid-state transformer
CN102185532A (en) * 2011-05-16 2011-09-14 武汉纺织大学 Grid-connected and off-grid hybrid solar energy photovoltaic generating system
CN202043052U (en) * 2011-05-04 2011-11-16 山东鲁亿通智能电气股份有限公司 Intelligent photovoltaic inverter and power generating system with same

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7050311B2 (en) * 2003-11-25 2006-05-23 Electric Power Research Institute, Inc. Multilevel converter based intelligent universal transformer

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000010648A (en) * 1998-06-18 2000-01-14 Canon Inc Electric power controller, and photovoltaic power generation system using the same
CN1794549A (en) * 2006-01-01 2006-06-28 福州大学 Step-up high frequency link A-A transducer
US7679941B2 (en) * 2007-06-06 2010-03-16 General Electric Company Power conversion system with galvanically isolated high frequency link
CN101615847A (en) * 2009-07-23 2009-12-30 东南大学 Automatic voltage regulator based on electric power electric transformer
CN101777775A (en) * 2010-02-26 2010-07-14 东南大学 High-frequency isolation single-phase photovoltaic grid-connected system and control method thereof
CN101917126A (en) * 2010-07-30 2010-12-15 浙江大学 Voltage-equalizing and power-equalizing control method for multi-module cascade solid-state transformer
CN202043052U (en) * 2011-05-04 2011-11-16 山东鲁亿通智能电气股份有限公司 Intelligent photovoltaic inverter and power generating system with same
CN102185532A (en) * 2011-05-16 2011-09-14 武汉纺织大学 Grid-connected and off-grid hybrid solar energy photovoltaic generating system

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Xu She等.Performance evaluation of solid state transformer based microgrid in FREEDM systems.《Applied Power Electronics Conference and Exposition(APEC),2011 Twenty-Sixth Annual IEEE》.2011, *
应用于新型微网FREEDM的固态变压器研究;刘金辉等;《电力系统及其自动化》;20100331;第32卷(第6期);第48页-53页 *

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